Egglaying 101 and then some...

I have a few things that I would like answered. I want to preface my questions by saying that I have a backyard flock of 8 (6 dominique hens, 1 dominique cockerel, and 1 dark brahma bantam cockerel). This is my first flock. The dominiques are all either full or half siblings to one another. Lastly, all of my chickens are 3 months old, including the banty. All that being said, I have some questions:

1) When my hens are ready to lay eggs, should I worry about hatching chicks from a rooster who is their brother? I mean, wouldn't you just have to pick up the eggs everyday to prevent a chick from growing in it?

2) Since all my chickens hatched and grew up together, would it be a problem if the six hens have two roosters with them? (The bantam and the dominique)? Will these two roosters hurt eachother soon as they get older?

3) Let's say I get rid of one of the roosters, would six hens be enough for one rooster?

Your eggs won't begin developing unless they are incubated, so collect eggs daily so you don't have to worry about it. First generation crosses with siblings is usually okay, it's only after repeated inbreeding that problems can develop.

Your two roosters will mostly get along with one dominant and one submissive, though more than likely they will both mate the hens, one after the other, this will cause your hens to be stressed and wear the feathers off their backs. I would remove one or rotate them if you wish to keep both, but I would not let both stay with them at the same time.

Every rooster is different, six may be okay and it may not, best to observe the roosters with the hens to determine if they are too much or not.